diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
index 1ce60852..c701359f 100644
--- a/.github/.OwlBot.lock.yaml
+++ b/.github/.OwlBot.lock.yaml
@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
-  digest: sha256:e7bb19d47c13839fe8c147e50e02e8b6cf5da8edd1af8b82208cd6f66cc2829c
-# created: 2022-07-05T18:31:20.838186805Z
+  digest: sha256:c6c965a4bf40c19011b11f87dbc801a66d3a23fbc6704102be064ef31c51f1c3
+# created: 2022-08-09T15:58:56.463048506Z
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index b46d7305..7092a139 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -10,7 +10,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v3
     - name: Setup Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: "3.10"
     - name: Install nox
@@ -26,7 +26,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v3
     - name: Setup Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: "3.10"
     - name: Install nox
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index f512a496..d2aee5b7 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -10,7 +10,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v3
     - name: Setup Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: "3.10"
     - name: Install nox
diff --git a/.github/workflows/unittest.yml b/.github/workflows/unittest.yml
index 5531b014..87ade4d5 100644
--- a/.github/workflows/unittest.yml
+++ b/.github/workflows/unittest.yml
@@ -13,7 +13,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v3
     - name: Setup Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python }}
     - name: Install nox
@@ -39,7 +39,7 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v3
     - name: Setup Python
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: "3.10"
     - name: Install coverage
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 226118e6..ade1bc26 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,14 @@
 
 [1]: https://pypi.org/project/google-cloud-language/#history
 
+## [2.5.2](https://github.com/googleapis/python-language/compare/v2.5.1...v2.5.2) (2022-08-11)
+
+
+### Bug Fixes
+
+* **deps:** allow protobuf < 5.0.0 ([#349](https://github.com/googleapis/python-language/issues/349)) ([a9c90c3](https://github.com/googleapis/python-language/commit/a9c90c3706a0108db1b0f7924d02d54c507efaf4))
+* **deps:** require proto-plus >= 1.22.0 ([a9c90c3](https://github.com/googleapis/python-language/commit/a9c90c3706a0108db1b0f7924d02d54c507efaf4))
+
 ## [2.5.1](https://github.com/googleapis/python-language/compare/v2.5.0...v2.5.1) (2022-07-13)
 
 
diff --git a/README.rst b/README.rst
index ba9380d5..85553b43 100644
--- a/README.rst
+++ b/README.rst
@@ -55,18 +55,22 @@ Code samples and snippets live in the `samples/` folder.
 
 Supported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^
-Our client libraries are compatible with all current [active](https://devguide.python.org/devcycle/#in-development-main-branch) and [maintenance](https://devguide.python.org/devcycle/#maintenance-branches) versions of
+Our client libraries are compatible with all current `active`_ and `maintenance`_ versions of
 Python.
 
 Python >= 3.7
 
+.. _active: https://devguide.python.org/devcycle/#in-development-main-branch
+.. _maintenance: https://devguide.python.org/devcycle/#maintenance-branches
+
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Python <= 3.6
 
-If you are using an [end-of-life](https://devguide.python.org/devcycle/#end-of-life-branches)
+If you are using an `end-of-life`_
 version of Python, we recommend that you update as soon as possible to an actively supported version.
 
+.. _end-of-life: https://devguide.python.org/devcycle/#end-of-life-branches
 
 Mac/Linux
 ^^^^^^^^^
diff --git a/noxfile.py b/noxfile.py
index 94b2f9c2..cc39f3b8 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -334,7 +334,8 @@ def prerelease_deps(session):
 
     # Install all dependencies
     session.install("-e", ".[all, tests, tracing]")
-    session.install(*UNIT_TEST_STANDARD_DEPENDENCIES)
+    unit_deps_all = UNIT_TEST_STANDARD_DEPENDENCIES + UNIT_TEST_EXTERNAL_DEPENDENCIES
+    session.install(*unit_deps_all)
     system_deps_all = (
         SYSTEM_TEST_STANDARD_DEPENDENCIES
         + SYSTEM_TEST_EXTERNAL_DEPENDENCIES
@@ -363,12 +364,6 @@ def prerelease_deps(session):
 
     session.install(*constraints_deps)
 
-    if os.path.exists("samples/snippets/requirements.txt"):
-        session.install("-r", "samples/snippets/requirements.txt")
-
-    if os.path.exists("samples/snippets/requirements-test.txt"):
-        session.install("-r", "samples/snippets/requirements-test.txt")
-
     prerel_deps = [
         "protobuf",
         # dependency of grpc
@@ -405,11 +400,19 @@ def prerelease_deps(session):
     system_test_folder_path = os.path.join("tests", "system")
 
     # Only run system tests if found.
-    if os.path.exists(system_test_path) or os.path.exists(system_test_folder_path):
-        session.run("py.test", "tests/system")
-
-    snippets_test_path = os.path.join("samples", "snippets")
-
-    # Only run samples tests if found.
-    if os.path.exists(snippets_test_path):
-        session.run("py.test", "samples/snippets")
+    if os.path.exists(system_test_path):
+        session.run(
+            "py.test",
+            "--verbose",
+            f"--junitxml=system_{session.python}_sponge_log.xml",
+            system_test_path,
+            *session.posargs,
+        )
+    if os.path.exists(system_test_folder_path):
+        session.run(
+            "py.test",
+            "--verbose",
+            f"--junitxml=system_{session.python}_sponge_log.xml",
+            system_test_folder_path,
+            *session.posargs,
+        )
diff --git a/samples/snippets/api/requirements.txt b/samples/snippets/api/requirements.txt
index 08c8a785..773c3e1e 100644
--- a/samples/snippets/api/requirements.txt
+++ b/samples/snippets/api/requirements.txt
@@ -1,3 +1,3 @@
-google-api-python-client==2.50.0
-google-auth==2.7.0
+google-api-python-client==2.56.0
+google-auth==2.10.0
 google-auth-httplib2==0.1.0
diff --git a/samples/snippets/classify_text/requirements.txt b/samples/snippets/classify_text/requirements.txt
index f4013916..32c8e5a7 100644
--- a/samples/snippets/classify_text/requirements.txt
+++ b/samples/snippets/classify_text/requirements.txt
@@ -1,3 +1,3 @@
-google-cloud-language==2.4.3
-numpy==1.22.4; python_version > '3.7'
+google-cloud-language==2.5.1
+numpy==1.23.1; python_version > '3.7'
 numpy===1.21.4; python_version == '3.7'
diff --git a/samples/snippets/cloud-client/v1/requirements.txt b/samples/snippets/cloud-client/v1/requirements.txt
index 964e9dc4..ed1b691c 100644
--- a/samples/snippets/cloud-client/v1/requirements.txt
+++ b/samples/snippets/cloud-client/v1/requirements.txt
@@ -1 +1 @@
-google-cloud-language==2.4.3
+google-cloud-language==2.5.1
diff --git a/samples/snippets/generated-samples/v1/requirements.txt b/samples/snippets/generated-samples/v1/requirements.txt
index 964e9dc4..ed1b691c 100644
--- a/samples/snippets/generated-samples/v1/requirements.txt
+++ b/samples/snippets/generated-samples/v1/requirements.txt
@@ -1 +1 @@
-google-cloud-language==2.4.3
+google-cloud-language==2.5.1
diff --git a/samples/snippets/sentiment/requirements.txt b/samples/snippets/sentiment/requirements.txt
index 964e9dc4..ed1b691c 100644
--- a/samples/snippets/sentiment/requirements.txt
+++ b/samples/snippets/sentiment/requirements.txt
@@ -1 +1 @@
-google-cloud-language==2.4.3
+google-cloud-language==2.5.1
diff --git a/setup.py b/setup.py
index 5d27bfde..17866216 100644
--- a/setup.py
+++ b/setup.py
@@ -21,7 +21,7 @@
 
 name = "google-cloud-language"
 description = "Google Cloud Natural Language API client library"
-version = "2.5.1"
+version = "2.5.2"
 # Should be one of:
 # 'Development Status :: 3 - Alpha'
 # 'Development Status :: 4 - Beta'
@@ -29,8 +29,8 @@
 release_status = "Development Status :: 5 - Production/Stable"
 dependencies = [
     "google-api-core[grpc] >= 1.32.0, <3.0.0dev,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*",
-    "proto-plus >= 1.15.0, <2.0.0dev",
-    "protobuf >= 3.19.0, <4.0.0dev",
+    "proto-plus >= 1.22.0, <2.0.0dev",
+    "protobuf >= 3.19.0, <5.0.0dev",
 ]
 
 # Setup boilerplate below this line.
diff --git a/testing/constraints-3.7.txt b/testing/constraints-3.7.txt
index f61f150b..810c7cb3 100644
--- a/testing/constraints-3.7.txt
+++ b/testing/constraints-3.7.txt
@@ -5,5 +5,5 @@
 # e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0dev",
 # Then this file should have google-cloud-foo==1.14.0
 google-api-core==1.32.0
-proto-plus==1.15.0
+proto-plus==1.22.0
 protobuf==3.19.0